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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
Advanced Search

To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

36385 results found.

  1. GRB 230816A: SAO RAS optical observations
  2. IPN triangulation of GRB 230815B
  3. GRB 230816A: Nanshan/HMT optical afterglow detection
  4. GRB 230815A: SOAR/Goodman follow-up imaging
  5. GRB 230816A: Swift detection of a burst
  6. GRB 230815A: Swift-BAT refined analysis
  7. GRB 230815B: GECAM-B and GECAM-C detection of a burst
  8. GRB 230815B: AstroSat CZTI detection
  9. GRB230815A: Swift/UVOT upper limits
  10. GRB 230812B: GAD Observatory optical observations (upper limit)
  11. GRB 230815A: Swift-XRT refined Analysis
  12. GRB 230812B: iTelescope optical upper limit
  13. GRB 230812B: continued SAO RAS optical observation
  14. GRB230815A: BOOTES-6/DPRT optical upper limit
  15. GRB 230815A: Fermi GBM detection
  16. Swift GRB 230815A: Global MASTER-Net observations report
  17. Fermi GRB 230814A: Global MASTER-Net observations report
  18. GRB 230815A: Enhanced Swift-XRT position
  19. GRB 230812B: Iota Scorpii Observatory, La Spezia, Italy
  20. GRB 230812B: Tautenburg observations
  21. GRB 230815A: Swift detection of a burst
  22. GRB 230812B: AMI-LA radio detection of afterglow candidate
  23. GRB 230812B: continued AbAO optical afterglow observations
  24. GRB 230812B: Optical observaions from Rozhen Observatory
  25. GRB 230812B: Further Bassano Bresciano Observatory optical observations
  26. GRB 230812B: further SAO RAS optical observations
  27. GRB 230812B: Upper limits from a neutrino search with IceCube
  28. GRB 230812B: GRANDMA further observations of ZTF23aaxeacr candidate afterglow
  29. GRB 230814A: BALROG localization (Fermi Trigger 713732101 / GRB 230814788)
  30. GRB 230812B: CrAO ZTSh optical observations
  31. GRB 230814A: Fermi GBM Final Real-time Localization
  32. GRB 230812B: Koshka Zeiss-1000 optical observations
  33. GRB 230812B: GIT optical follow-up
  34. GRB 230812B: Leavitt Observatory optical observations
  35. GRB 230812B : optical observations from Observatoire de Haute-Provence
  36. GRB 230812B: Bassano Bresciano Observatory optical observations
  37. GRB 230812B: Faulkes Telescope North optical afterglow follow-up
  38. GRB 230812B: Osservatorio Astronomico "Nastro Verde" optical observation
  39. GRB 230812B: rest-frame energetics from Konus-Wind observation
  40. GRB 230812B: OASDG optical observations
  41. GRB 230812B: AbAO optical observations
  42. GRB 230812B: Spectroscopy from NOT
  43. GRB 230812B: Redshift from OSIRIS+/GTC
  44. GRB 230812B: Montarrenti Observatory optical observations
  45. GRB 230812B: SAO RAS optical observations
  46. GRB 230812B: Detected Optical Afterglow Candidate
  47. GRB 230812B: GMG - GRANDMA observations
  48. Konus-Wind detection of GRB 230812B
  49. GRB230812B: AGILE/MCAL detection
  50. GRB 230812B: GECAM-C observation of a very bright burst
  51. GRB 230812B: Swift-XRT afterglow detection
  52. GRB 230812: Swift/UVOT Detection
  53. GOTO confirmation and possible host galaxy of GRB230812B optical afterglow
  54. GRB 230812B: Zwicky Transient Facility Identifies Optical Afterglow Candidate of a Fermi GRB (Trigger 713559497)
  55. Fermi GRB 230812B: MASTER optical counterpart
  56. GRB 230812B: KAIT Optical Afterglow Candidate
  57. GRB 230812B: Improved Swift/XRT localization
  58. GRB 230812B: Preliminary Swift/XRT localization
  59. GRB 230812B: Fermi-LAT detection
  60. GRB 230812B: Fermi GBM Observation of a very bright burst
  61. Fermi GRB 230812B: Global MASTER-Net observations report
  62. GRB 230812B: Tiled Swift observations
  63. GRB 230812B: Fermi GBM detection of an extremely bright GRB
  64. GRB 230812B: Fermi GBM Final Real-time Localization
  65. ZTF23aaoohpy/AT2023lcr: JWST spectroscopy confirmation of an associated type Ic-BL supernova
  66. GRB 230812A: Fermi GBM Final Real-time Localization
  67. GRB 230808A: Fermi GBM Detection
  68. GRB 230805B: Swift-BAT refined analysis
  69. GRB 230805B: Iota Scorpii Observatory, La Spezia, Italy upper limit
  70. GRB 230805B: AstroSat CZTI detection
  71. GRB 230808A: Swift/BAT-GUANO detection of a burst
  72. GRB 230808B: Fermi GBM Final Real-time Localization
  73. ZTF23aaoohpy/AT2023lcr: JWST observations consistent with the presence of a supernova
  74. GRB 230808A: Fermi GBM Final Real-time Localization
  75. GRB 230805B : MITSuME Akeno optical upper limits
  76. Fermi GRB 230807A: Global MASTER-Net observations report
  77. GRB 230807A: Fermi GBM Final Real-time Localization
  78. LIGO/Virgo/KAGRA S230805x: Upper limits from Swift/BAT-GUANO
  79. Konus-Wind detection of GRB 230803A
  80. GRB 230805B: Fermi GBM observation
  81. GRB 230805B : OHP/T193 optical upper limit
  82. GRB 230806A: Fermi GBM Final Localization
  83. GRB 230805B: Enhanced Swift-XRT position
  84. GRB 230805B: Swift/UVOT Upper Limits
  85. GRB 230805B: Bassano Bresciano observatory upper limit
  86. GRB 230805B: BOOTES-6/DPRT optical upper limit and 1.5m OSN detection
  87. GRB 230805B: NOT optical afterglow confirmation
  88. GRB 230805B: Swift-XRT refined Analysis
  89. Fermi GRB 230805A: Global MASTER-Net observations report
  90. GRB 230805B: SAO RAS optical observations
  91. Swift GRB 230805B: Global MASTER-Net observations report
  92. GRB 230805B: Swift detection of a burst
  93. GRB 230805A: Fermi GBM Final Real-time Localization
  94. GRB 230802B: AstroSat CZTI detection
  95. GRB 230802A: Fermi GBM observation
  96. GRB 230802A: Swift-BAT refined analysis
  97. GRB 230804A: Fermi GBM Final Real-time Localization
  98. IPN triangulation of GRB 230803A
  99. GRB 230802A: Swift/UVOT Upper Limits
  100. GRB 230803A: AstroSat CZTI detection

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